/**
 * @description: clear
 * @author: qianwenyu (16/03/08)
 * @update:
 */
@mixin clear($extend: true) {
  @if $extend {
    @extend %clear;
  }
  @else {
    &:before,
    &:after {
      content: "";
      display: table;
    }
    &:after {
      clear: both;
    }
  }
}

%clear {
  @include clear(false);
}
